Method of making textile materials



Patented June 6, 1939 PATENT OFFICE METHOD OF TEXTILE MATERIALS Camille Dreyfus, New York, N. Y., and William Whitehead, Cumberland, Md., assignors to Celanese Corporation of America, a. corporation of Delaware No Drawing. Application March 3, 1936, Serial No. 66,870

10 Claims.

This invention relates to the production of textile materials containing organic derivatives of cellulose that have an affinity for acid and neutral dyestuffs, and to such textile materials colored with dyestuffs normally having no affinity therefor.

An object of the invention is the economic and expeditious production of textile materials, containing an organic derivative of cellulose, that m are colored or have the property of being colored by dyestuffs that have no afiinity for normally prepared textile materials containing an organic derivative of cellulose. Another object of the invention is the production of textile materials 5 containing an organic derivative of cellulose that may be colored by dyestuffs having an alfinity for normally prepared organic derivatives of cellulose and also by direct, acid and neutral dyeing dyestuffs (cotton dyestuffs). Other objects of the invention will appear from the following detailed description.

Textile materials formed of an organic derivative of cellulose by the methods employed prior to this invention could not be permanently colored by a majority of the dyestuffs employed for the coloration of cotton. However, by various methods of saponification and de-etherification of the organic derivatives of cellulose they have been modified, in chemical composition, to a form in which they have an afiinity for cotton dyestuffs. As the organic derivatives of cellulose were modified to increase their affinity for cotton dyestuffs there was also a decrease in the affinity for dyestuffs having the property of dyeing the unmodified organic derivatives of cellulose. We have now found that if certain colloidal substances are incorporated with the organic derivative of cellulose they may be dyed with both cotton dyestuffs and dyestuffs having o the property of dyeing unmodified organic derivatives of cellulose.

By employing this invention, fabrics, yarns, etc., containing both fibres or filaments of organic derivatives of cellulose and fibres or filaments -;.3 of cotton or wool, may be dyed by a single dyestuff, provided the dyestuff employed is an acid or neutral dyeing dyestuff. Cross dyeing effects may be produced, however, by dyeing such mixed textile materials with dyestuffs having an affinity for normally prepared organic derivatives of cellulose, which dyestuffs have no aflinity for cotton and wool.

A further advantage of this invention is the production of textile materials, containing chemically unmodified organic derivatives of cellulose,

that have no distinct melting point and have a very high scorching temperature. Yarns and other textile materials made in accordance with this invention have a scorching temperature from to 80 C. higher than those prepared by the normal method of preparing similar textile materials from organic derivatives of cellulose. The usual 5 second test with a six pound electrically heated iron shows that, whereas fabrics made from normally prepared cellulose acetate starts to stick to the iron at around 220 C. and shows a pronounced melting or fusion at 230 C., fabrics made from cellulose acetate yarn prepared in accordance with this invention shows no actual sticking to the iron and does not exhibit a well pronounced melting point at any temperature. It starts to scorch at 265 C. and over.

A still further advantage of this invention is that there is produced a yarn that is dull and semi-pigmented in appearance with a slight bluish fluorescence.

In accordance with our invention, we form textile materials, films and foils from organic derivatives of cellulose which contain from 3 to- 20% or more, based on the weight of the organic derivative of cellulose present, of an inorganic colloid that has the property of producing in the organic derivative of cellulose an aflinity for acid and neutral dyeing dyestuffs. The filaments, fibres, yarns, etc. may be formed from cellulose acetate containing from 3 to 20%, based on the Weight of the cellulose acetate present, of a silica gel in which the water present from its formation has been replaced by alcohol or ace tone.

This invention is applicable to the formation of yarns, filaments, straws, tapes, films, etc., and to fabrics woven, knitted, netted, knotted or otherwise formed from these materials. Fibres, filaments, etc., may be formed of any suitable organic derivative of cellulose, such as the organic acid esters of cellulose and the cellulose ethers or the mixed acid esters and others of cellulose. Examples of organic acid esters of cellulose are cellulose acetate, cellulose formate, cellulose propionate and cellulose butyrate; while examples of cellulose others are ethyl cellulose, methyl cellulose and benzy cellulose.

Any suitable colloid may be employed to give to the organic derivative of cellulose an affinity for acid and neutral dyeing dyestuffs, which dye-' stuffs, for the purpose of describing this invention, will hereafter be termed cotton dyestuffs. For instance, an inorganic colloidal material having the properties of silica gel may be employed.

These colloids are usually formed from aqueous solutions and retain fairly large quantities of water. The quantity of water may often be sufficient to produce detrimental effects in the spinning of the organic derivative of cellulose to which the gel has been added. It is, therefore, usually advisable to replace the water in the gel by acetone, methyl alcohol, ethyl alcohol or other reagent which is compatible with the organic de rivative of cellulose and the solvents employed in the spinning solutions.

As an example, but not as a limitation, the following example of preparing a suitable silica gel is given:

Example I 800 parts by Weight of sodium silicate are dissolved in 4,800 parts by weight of water and the solution placed in a cooled container and phenol phthalein added. Normal hydrochloric acid is stirred in rapidly until the color of the phenol phthalein has almost disappeared, i. e. 232 parts by weight of concentrated hydrochloric acid diluted with 2,500 parts by weight of Water. At this point gelatinization takes place. The material is then heated for about 1 hour at 50 to C. The material after heating is broken up into small pieces and washed by decantation with Water until it is free of chlorides. The resulting product is then Washed with absolute alcohol or acetone by decantation until substantially free of water. For instance, the gel may be Washed with absolute acetone until an analysis of the supernatant liquor by the Messenger method indicates about 98% acetone.

The silica gel or other colloid may be added to a solution of an organic derivative of cellulose in a volatile solvent and the mixture formed into fibres, filaments, films, etc. by extruding the same through suitable orifices into a setting medium such as an evaporative atmosphere or a precipitating bath. The amount of silica gel employed may vary from less than 3 to more than 20% on the Weight of the organic derivative of cellulose present. We have found that it is preferable to add from 12 to 20%, based on the weight of the organic derivative of cellulose present, of silica gel prepared in accordance with the above example.

Although the colloid may be added directly to the spinning solution, it is preferable first to form a lacquer chip which in turn is dissolved in the spinning solution. The lacquer chips may be made by any suitable method from a mixture of the silica gel and the organic derivative-of cellulose wherein the percentage of silica gel present is from 20 to 50% or more. For instance, the lacquer chips may be made by any of the methods described in application S. No. 749,180, filed October 20, 1934, and S. No. 752,258, November 9, 1934.

' For the purpose of describing the method of forming filaments suitable for yarns, the following example is given. It is to be understood, however, that the invention is not restricted to the example but that the example is given merely by Way of illustration.

Example II A suitable quantity of lacquer chips containing silica gel and a suitable quantity of cellulose acetate are mixed with acetone so that the resulting compound contains 25% of a mixture of cellulose acetate and silica gel dissolved in a 95/5 acetone-water solvent. The quantity of lacquer chips employed is sufiiciently large so that there is present in the solution 17%, based on the weight of the cellulose acetate present, of silica gel. This solution is then filtered through filter presses normally employed in the production of artificial yarns. The particle size of the solids is small enough that the solution may be filtered through normal filter dressings employed in the filtration of spinning solutions without any appreciable separation. The charge is then spun by a dry method of spinning into filaments. Yarn produced has a dull semi-pigmented appearance with a slight bluish fluorescent case.

The yarn formed in accordance with Example II, or by similar methods, may be dyed either with cotton dyestuffs or dyestuffs having aifinity for normally prepared organic derivatives of cellulose. For instance, the yarns maybe dyed with cotton dyestuffs such as azo diamine dyes. Examples of azo diamine dyes are cotton Blue FFB and Diamine Fast Blue FFB.

These yarns may also be dyed by dyestuffs having afiinity for normally prepared organic derivatives of cellulose. These dyestufis, for the purpose of describing this invention and in the appended claims, Will be termed dyestuffs for organic derivatives of cellulose. Examples of these dyestuffs may be found in U. S. Patent No. 1,716,721.

It is to be understood that the foregoing detailed description is given merely by Way of illustration and that many variations may be made therein without departing from the spirit of our invention.

Having described our invention, what we desire to secure by Letters Patent is:

1. In a method of manufacturing colored ar tificial textile materials containing an organic derivative of cellulose, the steps of forming the textile materials by spinning a solution comprising a volatile solvent, an organic derivative of cellulose and, silica gel into a solidifying medium and dyeing the said textile materials while in an unswollen condition with a cotton dyestuif.

2. In a method of manufacturing colored artificial textile materials containing cellulose acetate, the steps of forming the textile materials by spinning a solution comprising a volatile solvent, cellulose acetate and silica gel into a solidifying medium and dyeing the said textile materials while in an unswollen condition with a cotton dyestuff.

3. In a method of manufacturing colored artificial textile materials contining an organic derivative of cellulose, the steps of forming the textile materials by spinning a solution comprising a volatile solvent, an organic derivative of cellulose and from 3 to 20%, on the weight of the organic derivative of cellulose, of silica gel into a solidifying medium and dyeing the said textile materials while in an unswollen condition with a cotton dyestuff.

- 4. In a method of manufacturing colored artificial textile materials containing cellulose acetate, the steps of forming the textile materials by spinning a solution comprising a volatile solvent, cellulose acetate and from 3 to 20%, on the weight of the cellulose acetate, of silica gel into a solidifying medium and dyeing the said textile materials while in an unswollen condition with a cotton dyestuff.

5. In a method of manufacturing colored artificial textile materials containing an organic derivative of cellulose, the steps of forming the textile materials by spinning a solution comprising a volatile solvent, an organic derivative-of cellulose and silica gel substantially free from water into a solidifying medium and dyeing the said textile materials while inan unswollen condition with a cotton dyestufi.-

6. In a method of manufacturing colored artificial textile materials containing cellulose acetate, the steps of forming the textile materials by spinning a solution comprising a volatile solvent, cellulose acetate and silica gel substantially free from water into a solidifying medium and dyeing the said textile materials while in an unswollen condition with a cotton dyestuff.

'7. In a method of manufacturing colored artificial textile materials containing an organic derivative of cellulose, the steps of forming the textile materials by spinning a solution comprising a volatile solvent, an organic derivative of celluloseiand silica gel in which substantially all of the water is replaced by acetone into a solidifying medium and dyeing the said textile materials while in an unswollen condition with a cotton 8. In a method of manufacturing colored artificial textile materials containing cellulose acetate, the steps of forming the textile materials by spinning a solution comprising a volatile solvent, cellulose acetate and silica gel in which substantially all of the water is replaced by acetone into a solidifying medium and dyeing the said textile materials while in an unswollen condition with a cotton dyestuif.

9. In a method of manufacturing colored arti ficial textile materials containing acetone-soluble cellulose acetate, the steps of forming the textile materials by spinning a solution comprising a volatile solvent, acetone-soluble cellulose acetate and silica gel into a solidifying medium and dyeing the said textile materials while in an unswollen condition with a cotton dyestuff.

10. In a method of manufacturing colored artificial textile materials containing acetone-soluble cellulose acetate, the steps of forming the textile materials by spinning a solution comprising a volatile solvent, acetone-soluble cellulose acetate and silica gel in which substantially all of the water is replaced by acetone into a solidifying medium and dyeing the said textile materials while in an unswollen condition with a cotton dyestuff.

CAMILLE DREYFUS. WILLIAM WHITEHEAD. 

